Fixed Canny

This commit is contained in:
Andrey Kamaev 2012-02-21 11:16:49 +00:00
parent 5785a89053
commit ff2af7d8bb

View File

@ -50,68 +50,74 @@ void cv::Canny( InputArray _src, OutputArray _dst,
_dst.create(src.size(), CV_8U);
Mat dst = _dst.getMat();
if (!L2gradient && (aperture_size & CV_CANNY_L2_GRADIENT) == CV_CANNY_L2_GRADIENT)
{
//backward compatibility
aperture_size &= ~CV_CANNY_L2_GRADIENT;
L2gradient = true;
}
if ((aperture_size & 1) == 0 || (aperture_size != -1 && (aperture_size < 3 || aperture_size > 7)))
CV_Error(CV_StsBadFlag, "");
#ifdef HAVE_TEGRA_OPTIMIZATION
if (tegra::canny(src, dst, low_thresh, high_thresh, aperture_size, L2gradient))
return;
#endif
if( low_thresh > high_thresh )
const int cn = src.channels();
cv::Mat dx(src.rows, src.cols, CV_16SC(cn));
cv::Mat dy(src.rows, src.cols, CV_16SC(cn));
cv::Sobel(src, dx, CV_16S, 1, 0, aperture_size, 1, 0, cv::BORDER_REPLICATE);
cv::Sobel(src, dy, CV_16S, 0, 1, aperture_size, 1, 0, cv::BORDER_REPLICATE);
if (low_thresh > high_thresh)
std::swap(low_thresh, high_thresh);
if( (aperture_size & 1) == 0 || (aperture_size != -1 && (aperture_size < 3 || aperture_size > 7)) )
CV_Error( CV_StsBadFlag, "" );
Mat dx, dy;
Sobel(src, dx, CV_16S, 1, 0, aperture_size, 1, 0, BORDER_REFLECT_101);
Sobel(src, dy, CV_16S, 0, 1, aperture_size, 1, 0, BORDER_REFLECT_101);
int low, high;
if( L2gradient )
if (L2gradient)
{
Cv32suf ul, uh;
ul.f = (float)low_thresh;
uh.f = (float)high_thresh;
low = ul.i;
high = uh.i;
}
else
{
low = cvFloor( low_thresh );
high = cvFloor( high_thresh );
low_thresh = std::min(32767.0, low_thresh);
high_thresh = std::min(32767.0, high_thresh);
if (low_thresh > 0) low_thresh *= low_thresh;
if (high_thresh > 0) high_thresh *= high_thresh;
}
int low = cvFloor(low_thresh);
int high = cvFloor(high_thresh);
Size size = src.size();
int i, j, k, mstep = size.width + 2, cn = src.channels();
ptrdiff_t mapstep = src.cols + 2;
cv::AutoBuffer<uchar> buffer((src.cols+2)*(src.rows+2) + cn * mapstep * 3 * sizeof(int));
Mat mask(size.height + 2, mstep, CV_8U);
memset( mask.ptr<uchar>(0), 1, mstep );
memset( mask.ptr<uchar>(size.height+1), 1, mstep );
Mat mag(6+cn, mstep, CV_32S);
mag = Scalar::all(0);
int* mag_buf[3] = { mag.ptr<int>(0), mag.ptr<int>(1), mag.ptr<int>(2) };
short* dxybuf[3] = { (short*)mag.ptr<int>(3), (short*)mag.ptr<int>(4), (short*)mag.ptr<int>(5) };
int* mbuf = mag.ptr<int>(6);
int maxsize = MAX( 1 << 10, size.width*size.height/10 );
std::vector<uchar*> stack( maxsize );
uchar **stack_top, **stack_bottom;
stack_top = stack_bottom = &stack[0];
int* mag_buf[3];
mag_buf[0] = (int*)(uchar*)buffer;
mag_buf[1] = mag_buf[0] + mapstep*cn;
mag_buf[2] = mag_buf[1] + mapstep*cn;
memset(mag_buf[0], 0, /* cn* */mapstep*sizeof(int));
/* sector numbers
uchar* map = (uchar*)(mag_buf[2] + mapstep*cn);
memset(map, 1, mapstep);
memset(map + mapstep*(src.rows + 1), 1, mapstep);
int maxsize = std::max(1 << 10, src.cols * src.rows / 10);
std::vector<uchar*> stack(maxsize);
uchar **stack_top = &stack[0];
uchar **stack_bottom = &stack[0];
/* sector numbers
(Top-Left Origin)
1 2 3
* * *
* * *
* * *
* * *
0*******0
* * *
* * *
* * *
* * *
3 2 1
*/
#define CANNY_PUSH(d) *(d) = (uchar)2, *stack_top++ = (d)
#define CANNY_PUSH(d) *(d) = uchar(2), *stack_top++ = (d)
#define CANNY_POP(d) (d) = *--stack_top
// calculate magnitude and angle of gradient, perform non-maxima supression.
@ -119,217 +125,153 @@ void cv::Canny( InputArray _src, OutputArray _dst,
// 0 - the pixel might belong to an edge
// 1 - the pixel can not belong to an edge
// 2 - the pixel does belong to an edge
for( i = 0; i <= size.height; i++ )
for (int i = 0; i <= src.rows; i++)
{
int *_mag = mag_buf[(i > 0) + 1] + 1;
float* _magf = (float*)_mag;
const short *_dx, *_dy;
short *_ddx, *_ddy;
uchar* _map;
int x, y;
ptrdiff_t magstep1, magstep2;
int prev_flag = 0;
if( i < size.height )
int* _norm = mag_buf[(i > 0) + 1] + 1;
if (i < src.rows)
{
_dx = dx.ptr<short>(i);
_dy = dy.ptr<short>(i);
_ddx = dxybuf[(i > 0) + 1];
_ddy = _ddx + size.width;
if( cn > 1 )
short* _dx = dx.ptr<short>(i);
short* _dy = dy.ptr<short>(i);
if (!L2gradient)
{
_mag = mbuf;
_magf = (float*)_mag;
}
if( !L2gradient )
for( j = 0; j < size.width*cn; j++ )
_mag[j] = std::abs(_dx[j]) + std::abs(_dy[j]);
else
{
for( j = 0; j < size.width*cn; j++ )
{
x = _dx[j]; y = _dy[j];
_magf[j] = sqrtf((float)x*x + (float)y*y);
}
}
if( cn > 1 )
{
_mag = mag_buf[(i > 0) + 1] + 1;
for( j = 0; j < size.width; j++ )
{
_mag[j] = mbuf[(j+1)*cn];
_ddx[j] = _dx[j*cn]; _ddy[j] = _dy[j*cn];
}
for( k = 1; k < cn; k++ )
{
for( j = 0; j < size.width; j++ )
if( mbuf[(j+1)*cn + k] > _mag[j] )
{
_mag[j] = mbuf[(j+1)*cn + k];
_ddx[j] = _dx[j*cn + k];
_ddy[j] = _dy[j*cn + k];
}
}
for (int j = 0; j < src.cols*cn; j++)
_norm[j] = std::abs(int(_dx[j])) + std::abs(int(_dy[j]));
}
else
{
for( j = 0; j < size.width; j++ )
_ddx[j] = _dx[j]; _ddy[j] = _dy[j];
for (int j = 0; j < src.cols*cn; j++)
_norm[j] = int(_dx[j])*_dx[j] + int(_dy[j])*_dy[j];
}
_mag[-1] = _mag[size.width] = 0;
if (cn > 1)
{
for(int j = 0, jn = 0; j < src.cols; ++j, jn += cn)
{
int maxIdx = jn;
for(int k = 1; k < cn; ++k)
if(_norm[jn + k] > _norm[maxIdx]) maxIdx = jn + k;
_norm[j] = _norm[maxIdx];
_dx[j] = _dx[maxIdx];
_dy[j] = _dy[maxIdx];
}
}
_norm[-1] = _norm[src.cols] = 0;
}
else
memset( _mag-1, 0, (size.width + 2)*sizeof(_mag[0]) );
memset(_norm-1, 0, /* cn* */mapstep*sizeof(int));
// at the very beginning we do not have a complete ring
// buffer of 3 magnitude rows for non-maxima suppression
if( i == 0 )
if (i == 0)
continue;
_map = &mask.at<uchar>(i, 1);
_map[-1] = _map[size.width] = 1;
_mag = mag_buf[1] + 1; // take the central row
_dx = dxybuf[1];
_dy = _dx + size.width;
magstep1 = mag_buf[2] - mag_buf[1];
magstep2 = mag_buf[0] - mag_buf[1];
uchar* _map = map + mapstep*i + 1;
_map[-1] = _map[src.cols] = 1;
if( (stack_top - stack_bottom) + size.width > maxsize )
int* _mag = mag_buf[1] + 1; // take the central row
ptrdiff_t magstep1 = mag_buf[2] - mag_buf[1];
ptrdiff_t magstep2 = mag_buf[0] - mag_buf[1];
const short* _x = dx.ptr<short>(i-1);
const short* _y = dy.ptr<short>(i-1);
if ((stack_top - stack_bottom) + src.cols > maxsize)
{
int sz = (int)(stack_top - stack_bottom);
maxsize = MAX( maxsize * 3/2, maxsize + size.width );
maxsize = maxsize * 3/2;
stack.resize(maxsize);
stack_bottom = &stack[0];
stack_top = stack_bottom + sz;
}
for( j = 0; j < size.width; j++ )
int prev_flag = 0;
for (int j = 0; j < src.cols; j++)
{
#define CANNY_SHIFT 15
#define TG22 (int)(0.4142135623730950488016887242097*(1<<CANNY_SHIFT) + 0.5)
const int TG22 = (int)(0.4142135623730950488016887242097*(1<<CANNY_SHIFT) + 0.5);
x = _dx[j];
y = _dy[j];
int s = x ^ y;
int m = _mag[j];
x = std::abs(x);
y = std::abs(y);
if( m > low )
if (m > low)
{
int xs = _x[j];
int ys = _y[j];
int x = std::abs(xs);
int y = std::abs(ys) << CANNY_SHIFT;
int tg22x = x * TG22;
int tg67x = tg22x + ((x + x) << CANNY_SHIFT);
y <<= CANNY_SHIFT;
if( y < tg22x )
if (y < tg22x)
{
if( m > _mag[j-1] && m >= _mag[j+1] )
{
if( m > high && !prev_flag && _map[j-mstep] != 2 )
{
CANNY_PUSH( _map + j );
prev_flag = 1;
}
else
_map[j] = (uchar)0;
continue;
}
}
else if( y > tg67x )
{
if( m > _mag[j+magstep2] && m >= _mag[j+magstep1] )
{
if( m > high && !prev_flag && _map[j-mstep] != 2 )
{
CANNY_PUSH( _map + j );
prev_flag = 1;
}
else
_map[j] = (uchar)0;
continue;
}
if (m > _mag[j-1] && m >= _mag[j+1]) goto __ocv_canny_push;
}
else
{
s = s < 0 ? -1 : 1;
if( m > _mag[j+magstep2-s] && m > _mag[j+magstep1+s] )
int tg67x = tg22x + (x << (CANNY_SHIFT+1));
if (y > tg67x)
{
if( m > high && !prev_flag && _map[j-mstep] != 2 )
{
CANNY_PUSH( _map + j );
prev_flag = 1;
}
else
_map[j] = (uchar)0;
continue;
if (m > _mag[j+magstep2] && m >= _mag[j+magstep1]) goto __ocv_canny_push;
}
else
{
int s = (xs ^ ys) < 0 ? -1 : 1;
if (m > _mag[j+magstep2-s] && m > _mag[j+magstep1+s]) goto __ocv_canny_push;
}
}
}
prev_flag = 0;
_map[j] = (uchar)1;
_map[j] = uchar(1);
continue;
__ocv_canny_push:
if (!prev_flag && m > high && _map[j-mapstep] != 2)
{
CANNY_PUSH(_map + j);
prev_flag = 1;
}
else
_map[j] = 0;
}
// scroll the ring buffers
// scroll the ring buffer
_mag = mag_buf[0];
mag_buf[0] = mag_buf[1];
mag_buf[1] = mag_buf[2];
mag_buf[2] = _mag;
_ddx = dxybuf[0];
dxybuf[0] = dxybuf[1];
dxybuf[1] = dxybuf[2];
dxybuf[2] = _ddx;
}
// now track the edges (hysteresis thresholding)
while( stack_top > stack_bottom )
while (stack_top > stack_bottom)
{
uchar* m;
if( (stack_top - stack_bottom) + 8 > maxsize )
if ((stack_top - stack_bottom) + 8 > maxsize)
{
int sz = (int)(stack_top - stack_bottom);
maxsize = MAX( maxsize * 3/2, maxsize + 8 );
maxsize = maxsize * 3/2;
stack.resize(maxsize);
stack_bottom = &stack[0];
stack_top = stack_bottom + sz;
}
CANNY_POP(m);
if( !m[-1] )
CANNY_PUSH( m - 1 );
if( !m[1] )
CANNY_PUSH( m + 1 );
if( !m[-mstep-1] )
CANNY_PUSH( m - mstep - 1 );
if( !m[-mstep] )
CANNY_PUSH( m - mstep );
if( !m[-mstep+1] )
CANNY_PUSH( m - mstep + 1 );
if( !m[mstep-1] )
CANNY_PUSH( m + mstep - 1 );
if( !m[mstep] )
CANNY_PUSH( m + mstep );
if( !m[mstep+1] )
CANNY_PUSH( m + mstep + 1 );
if (!m[-1]) CANNY_PUSH(m - 1);
if (!m[1]) CANNY_PUSH(m + 1);
if (!m[-mapstep-1]) CANNY_PUSH(m - mapstep - 1);
if (!m[-mapstep]) CANNY_PUSH(m - mapstep);
if (!m[-mapstep+1]) CANNY_PUSH(m - mapstep + 1);
if (!m[mapstep-1]) CANNY_PUSH(m + mapstep - 1);
if (!m[mapstep]) CANNY_PUSH(m + mapstep);
if (!m[mapstep+1]) CANNY_PUSH(m + mapstep + 1);
}
// the final pass, form the final image
for( i = 0; i < size.height; i++ )
const uchar* pmap = map + mapstep + 1;
uchar* pdst = dst.ptr();
for (int i = 0; i < src.rows; i++, pmap += mapstep, pdst += dst.step)
{
const uchar* _map = mask.ptr<uchar>(i+1) + 1;
uchar* _dst = dst.ptr<uchar>(i);
for( j = 0; j < size.width; j++ )
_dst[j] = (uchar)-(_map[j] >> 1);
for (int j = 0; j < src.cols; j++)
pdst[j] = (uchar)-(pmap[j] >> 1);
}
}